Recently, vehicle navigation systems have become more popular and affordable for most vehicle drivers. The navigation system can, not only determine the driver's current position by utilizing the Global Positioning System (GPS), but also provide different routing information between the vehicle's current position and the destination. In order to perform above noted functions, the navigation system is usually equipped with navigation computer programs and one or more detailed database to store and provide maps, road networks, geographical features, waypoints, and point-of-interest (POI) information.
A “waypoint” is defined as an intermediate point (intermediate destination or tentative destination) on a route or a line of travel. Sometimes, when driving on a planned (calculated) route produced by the navigation system, the driver may want to stop-by somewhere along the route (i.e. waypoint) before reaching the final destination. Most navigation systems are capable of recalculating the route and providing the driver a new route to the waypoint, then to the destination.
However, as illustrated in FIG. 1, after a waypoint POI 101 (e.g. ABC Seafood) is specified by the driver in a navigation system 100, the driver has to click on an “Options” button 102 on a screen 110 and a “Set as Waypoint” button on a screen 120, to finalize the waypoint setting. This waypoint setting process may be inconvenient and time-consuming for the driver, especially the first-time user of the navigation system, to figure out how to set the POI 101 as a waypoint. Furthermore, if the driver operates the navigation system 100 while driving, this waypoint setting process may significantly increase the possibility of driver distraction from the safe driving.
To solve the problems involved in the conventional example of FIG. 1, a system 200 has been developed to automatically set a POI as a waypoint as shown in FIG. 2. The system of FIG. 2 shows another conventional example involved in the navigation system to select a waypoint to visit before reaching the final destination. In viewing a screen 210, the driver starts the waypoint setting process by clicking an “Along Route” button 211.
Then, the navigation system 200 shows a screen 220 which lists categories of POIs as shown at about the middle of FIG. 2. Thus, the driver is able to further select the POI category 221 (e.g. Restaurant) from the list. In response to the POI category input by the driver, the navigation system 200 then provides detailed POI information (e.g. Restaurant names, telephone numbers, distances, etc.) to the driver on a screen 230.
Based on the detailed information, the driver can select a desired POI as a waypoint. Once a specific POI (e.g. McDonald) 231 is selected, the navigation system 200 automatically sets the POI 231 as the waypoint (a tentative destination before the final destination). With fewer steps in waypoint setting, this system not only reduces the possibility of driver distraction, but also provides a convenient and efficient means for waypoint setting.
However, some problems may occur in the above mentioned waypoint setting procedure for the navigation system. For example, as shown in FIG. 2a, when a POI 204 is located even further than a destination 202 (from a starting point 201), it is unrealistic and unreasonable to automatically set the POI 204 as the waypoint since the distance to the POI 204 is much longer (203 plus 205) than the distance (203) to the destination 202. Thus, instead of setting the POI 204 as the waypoint automatically, the navigation system should be able to calculate and compare the distances to the destination 202 and to the POI 204. Then, the navigation system should provide routing information to the driver so that the driver can be notified to make a judgement so as to avoid unnecessary routing, especially when the gas price is so high in the present time.
Likewise, as can be seen in FIG. 2b, even though the distance (206) to the POI 204 from the starting point 201 seems shorter than the originally planned route 203, adding the POI 204 as the waypoint may significantly increase the total route (206 plus 207) to the destination 202. As mentioned above, in such a situation, the navigation system should be capable of calculating and comparing the routes, and the driver should be notified about the routing information to avoid the unnecessary routing.
U.S. Pat. No. 6,975,938 issued to Odagawa et al. discloses a drive plan producing device to generate a tour plan, which is automatically produced to cover the plurality of candidate places obtained based on the base contents within a predetermined range. However, when adding a candidate place may significantly increase the route, the navigation system of Odagawa et al. does not provide any notifying message to the driver to decide whether to proceed to the candidate place. Also, the system of Odagawa et al. does not allow the driver to prioritize the candidate places based on the driver's preference
U.S. Pat. No. 6,278,938 issued to Alumbaugh discloses a navigation system which provides a function to automatically collect, analyze and refine the waypoints for their intended purposes. However, like the Odagawa et al. '938 patent discussed above, when adding the waypoint may significantly increase the overall length of the route, the navigation system of Alumbaugh does not provide any notifying message to the driver to decide whether to proceed to the waypoint or not. In addition, when there are multiple waypoints, the navigation system of Alumbaugh does not allow the driver to prioritize the waypoints based on the driver's preference.
Therefore, there remains a need for a new and improved route planning apparatus and method for a navigation system which allows the driver to add, select, and prioritize the waypoints such as POIs, and provides a notifying message to let the driver know when adding the waypoint or POI would significantly increase the overall distance of the route.